Various types of tractor mounted row markers swingable from one side of the tractor to another have been heretofore designed, some of which previous devices are disclosed in U.S. Pat. Nos. 188,624, 1,616,099, 2,341,146, 2,483,011, 2,850,958, 3,762,482 and 3,774,690. However, some of these previous row markers may not be swung to a trailing position disposed along one side of the tractor during transport of the latter from one location to another and other previously known row markers may not be readily swung from one side of the tractor to the other. Still further, some previously known row markers require mounting at the rear of the associated tractor and, therefore, are not readily observed by the operator of the associated tractor unless the operator turns his head fully to one side.